1. Field of the Invention
The present invention relates to a shutter release unit that is incorporated in a camera and swung in accordance with shutter release operation, for activating plural devices for photography.
2. Background Arts
In order to reduce manufacturing cost of a camera, it is preferable to furnish a camera component with multiple functions. For example, a shutter release member is well-known in a compact camera, wherein the shutter release member includes a shutter button and a shutter release lever for actuating a shutter release mechanism of the camera.
U.S. Pat. No. 5,867,742 discloses a shutter release member which is coupled to a camera body in a slidable fashion. The shutter release member is comprised of a shutter button arm, a shutter actuation arm and an electrical contact arm, which are provided integrally with a sliding member movably coupled to the camera body. The electrical contact arm includes electrical contact elements. The sliding member is biased by a spring member to an initial position. When an user depressed the shutter button arm against the bias of the spring member, the sliding member is slid down from the initial position. Then, the shutter actuation arm interacts with a shutter lock member to activate a shutter release mechanism. Thereby, a subject image is exposed to a photo filmstrip. Concurrently, the electrical contact arm is also slid, and the electrical contact elements come in contact with electrical contact pads provided on a circuit board that is coupled to the camera body. Thereby, an electrical device, such as a flash control circuit, is activated to carry out electrical operation.
Meanwhile, in case of night or indoor photography of a person with the pupil of the eye fully open, red-eye effect is likely to occur, by which person""s eyes on a print are colored red like rabbit""s eyes. In order to prevent the red-eye effect, it is desirable to make a red-eye reduction device for emitting weak light prior to emission of flash light, for shrinking pupils. Most compact cameras have such a red-eye reduction device as well as flash device. The compact camera also includes a film winding mechanism including a feeding motor, which is automatically driven to feed the photo filmstrip frame by frame after photography. These red-eye reduction device and film winding mechanism are sequentially controlled by use of a microcomputer.
In order to reduce manufacturing cost of the compact camera, it is preferable to assign switches for activating the devices, such as the red-eye reduction device and the film winding mechanism, to the shutter release member. In case of applying the multi functional shutter release unit disclosed in the above U.S. Patent, however, the electrical contact arm is required to be positioned with high accuracy for enabling sequential operation of the camera. Accordingly, it is difficult to provide such a release button member with a compact camera of low-cost type.
Moreover, in the shutter release unit of the above U.S. Patent, a spring member is needed for biasing the shutter release unit toward the initial position. In order to prevent increase in manufacturing cost, it is desirable to decrease parts number by omitting the spring member.
In view of the foregoing, an object of the present invention is to provide a shutter release unit for enabling sequential operation of the preliminary flash emission mechanism and the film feeding mechanism without increasing manufacturing cost.
To achieve the above objects, a shutter release unit of the present invention comprises an unit holder, a lever rotatably attached to the unit holder, and a shutter button, a shutter actuation member and a biasing member, which are integrated in the lever. The shutter button is exposed through an opening formed in a housing of the camera. When the shutter button is depressed, the lever and the shutter actuation member are rotated to carry out shutter release operation.
The unit holder is attached to a lens covering member which covers a lens holder for securing a taking lens of the camera. Since the lever is not attached directly to the main body of the camera, it is possible to design the camera configuration more freely. The unit holder may be attached to the lens holder or the housing.
The biasing member is bent to form an L-shape, and an end portion thereof comes in contact with an inner wall of the housing. Thus, the biasing member is resiliently deformed in accordance with depression of the shutter button, so that the shutter button is biased toward an initial position. Since the biasing member is integrated in the lever, it is possible to reduce manufacturing cost by omitting a spring.
The shutter release unit includes a switch arm, which is positioned further from a pivot of the lever than the shutter button. The switch arm is rotated from a first position to a second position in accordance with depression of the shutter button. Plural electrical contact arms are mounted on an end portion of the switch arm. The electrical contact arms come in contact with plural electrical contact pads provided on a printed circuit board, on which a plurality of electric circuits for driving a red-eye reduction device, a film winding mechanism and so forth are mounted. When the shutter button is depressed, the switch arm is moved to the second position. Then, contacting condition between the between said electrical contact arms and said electrical contact pads is switched, so the red-eye reduction device is activated. When the shutter button is returned back to the first position, the contacting condition is switched again, so the film winding mechanism is activated to feed a photo filmstrip by one frame.